Buggy code:
void updateBackground ( boolean dark ) { } void updateIcon ( Job job ) { } } abstract class JobTreeItem extends Canvas implements Listener { boolean jobTerminated ; JobTreeElement jobTreeElement ; boolean keepItem ; JobTreeItem ( Composite parent , JobTreeElement info , int flags ) { } boolean checkKeep ( ) { } protected void dump ( String message ) { } Job getJob ( ) { } public void handleEvent ( Event e ) { } void init ( JobTreeElement info ) { } public boolean kill ( ) { } abstract boolean refresh ( ) { } public boolean remove ( ) { } void setKeep ( ) { } void setKept ( ) { } } class ListLayout extends Layout { static final int VERTICAL_SPACING = 1 ; boolean refreshBackgrounds ; protected Point computeSize ( Composite composite , int wHint , int hHint , boolean flushCache ) { } protected void layout ( Composite composite , boolean flushCache ) { } } static final boolean DEBUG = false ; private static String ELLIPSIS = ProgressMessages . ProgressFloatingWindow_EllipsisValue ; static final QualifiedName ICON_PROPERTY = IProgressConstants . ICON_PROPERTY ; static final boolean isCarbon = "carbon" . equals ( SWT . getPlatform ( ) ) ; static final QualifiedName KEEP_PROPERTY = IProgressConstants . KEEP_PROPERTY ; static final QualifiedName KEEPONE_PROPERTY = IProgressConstants . KEEPONE_PROPERTY ; static String shortenText ( Control control , String textValue ) { } static String shortenText ( GC gc , int maxWidth , String textValue ) { } private Font boldFont ; private Image cancelJobIcon ; private Image cancelJobDIcon ; private Image clearJobIcon ; private Image clearJobDIcon ; private Color darkColor ; private Image defaultJobIcon ; private boolean dialogContext ; private FinishedJobs finishedJobs ; private Cursor handCursor ; private NewProgressViewer . JobTreeItem highlightItem ; private Job highlightJob ; private Color lightColor ; private Composite list ; private HashMap map = new HashMap ( ) ; private Cursor normalCursor ; private ScrolledComposite scroller ; private Color selectedColor ; private Color selectedTextColor ; private Font smallerFont ; private Color textColor ; public NewProgressViewer ( Composite parent , int flags ) { } public void add ( Object parentElement , Object [ ] elements ) { } protected void addTreeListener ( Control c , TreeListener listener ) { } public void cancelSelection ( ) { } void clearAll ( ) { } Object [ ] contentProviderGetChildren ( Object parent ) { } Object [ ] contentProviderGetRoots ( Object parent ) { } protected void createChildren ( Widget widget ) { } private NewProgressViewer . JobItem createItem ( Object element ) { } void doSelection ( ) { } protected void doUpdateItem ( final Item item , Object element ) { } private boolean filtered ( Object element ) { } private NewProgressViewer . JobTreeItem findJobItem ( Object element , boolean create ) { } public void finished ( JobTreeElement jte ) { } private void forcedRemove ( final JobTreeElement jte ) { } private Color getActiveHyperlinkColor ( ) { } protected Item [ ] getChildren ( Widget o ) { } public Control getControl ( ) { } private Font getDefaultFont ( ) { } private FontData [ ] getDefaultFontData ( ) { } private Color getErrorColor ( ) { } protected boolean getExpanded ( Item item ) { } private String getFinishedString ( JobTreeElement jte , String name , boolean withTime ) { } private Color getHighlightColor ( ) { } private Color getHyperlinkColor ( ) { } protected Item getItem ( int x , int y ) { } protected int getItemCount ( Control widget ) { } protected int getItemCount ( Item item ) { } protected Item [ ] getItems ( Item item ) { } private String getJobNameAndStatus ( JobInfo ji , Job job , boolean terminated , boolean withTime ) { } protected Item getParentItem ( Item item ) { } public ISelection getSelection ( ) { } protected Item [ ] getSelection ( Control widget ) { } private Control [ ] getSortedChildren ( ) { } private String getTimeString ( JobTreeElement jte ) { } public Tree getTree ( ) { } protected void internalRefresh ( Object element , boolean updateLabels ) { } private boolean jobFiltered ( JobInfo ji ) { Job job = ji . getJob ( ) ; if ( ( job != null ) && ( job == ( highlightJob ) ) ) return false ; if ( ( job == null ) || ( ( job . getState ( ) ) == ( Job . SLEEPING ) ) ) return true ; if ( job . isSystem ( ) ) { if ( ( getContentProvider ( ) ) instanceof ProgressContentProvider ) <START_BUG> return ( ( ProgressContentProvider ) ( getContentProvider ( ) ) ) . filterDebug ; <END_BUG> return false ; } return false ; } protected Item newItem ( Widget parent , int flags , int ix ) { } public void refresh ( boolean updateLabels ) { } public void refresh ( Object element , boolean updateLabels ) { } private void relayout ( boolean layout , boolean refreshBackgrounds ) { } public void remove ( Object [ ] elements ) { } protected void removeAll ( Control widget ) { } public void removed ( final JobTreeElement info ) { } public void reveal ( NewProgressViewer . JobTreeItem jti ) { } private void select ( NewProgressViewer . JobItem newSelection , Event e ) { } protected void setExpanded ( Item node , boolean expand ) { } public void setFocus ( ) { } public void setHighlightJob ( Job job ) { } public void setInput ( IContentProvider provider ) { } public void setSelection ( ISelection selection ) { } protected void setSelection ( List items ) { } public void setUseHashlookup ( boolean b ) { } protected void showItem ( Item item ) { } private String stripPercent ( String s ) { } }

Fix:
return ! ( ( ( ProgressContentProvider ) ( getContentProvider ( ) ) ) . debug ( ) ) ;